1. Field of the Invention
The present invention relates generally to a content transmission system, and more particularly, to an apparatus and method for providing an additional service such as a next-generation user-customized service by analyzing a user content consumption pattern.
2. Description of the Related Art
The mobile communication market is continuously requested to produce new services by recombining or integrating existing technologies. In line with the recent development of communication and broadcasting technologies, conventional broadcasting systems or mobile communication systems can now provide next-generation user-customized services through portable terminals, such as cellular phones, Personal Digital Assistants (PDAs), and the like (terminals).
It is expected that a service for measuring a user consumption pattern and providing content or advertisements suitable for a user's tastes will be widely used in a broadcasting service or a content providing service as one of the next-generation user-customized services. A basic function of the service is Audience Measurement (AM). The basic function of AM records what services are consumed by a user, when the user consumes services, where the user consumes the services, how long the user consumes the services, and how the user consumes the services. The operation of AM includes AM command delivery, AM execution, and AM execution result reporting. AM data may be stored in a device for consuming content or a server managed by a service provider. The AM may be stored directly by an operator for operating a content transmission service or a third AM related operator on a network. Thus, terminals or smart cards for executing AM should be able to transmit an AM execution result report to an address of a server indicated by an AM command.
As mentioned above, AM may be implemented directly in a terminal or in a smart card connected to such terminal. When AM is implemented directly in a terminal, a timer or an embedded watch in the terminal may directly measure the consumption time of a service and content. On the other hand, when the AM function is embedded in a smart card, the consumption time of the service and the content cannot be directly measured. During the consumption of services or content, smart cards have been introduced in order to ensure the proper user has access and a service/content transmission path and a content protection function of preventing illegal use of content. In the service protection function, the smart card stores decryption keys for decrypting content and services encrypted through service protection and delivers the decryption keys to a terminal at the request of the terminal when the terminal tries to decrypt the encrypted content and services, thereby allowing the content and services to be decrypted and available to the user. The smart card having the embedded AM function uses a method of estimating a consumption time of content and a service by using a message which requests delivery of a decryption key for decrypting the content and the service when the terminal needs the decryption key.
In the foregoing conventional technique, when an AM server is managed by the same operator managing a server for providing the service protection function, a consumption time of a service or content can be estimated by using a frequency of a message used for a terminal to request a smart card to deliver a decryption key. However, when the AM server is managed by a third operator, there is no way for a smart card with an embedded AM function to report a consumption time of a service and content. Therefore, there is a need for a scheme capable of reporting a consumption time of a service and content in the smart card having an embedded AM function therein.